Stuffplug NG is a plug in for Messenger Plus!. Messenger Discovery is a stand alone program, so they are very different
if u already use plus! i would suggest u stuffplug.
i havent tested Messenger Discovery myself so i dunno, many people here dont like it.. i think u should try both programs and decide for the one u like the most (or both of them, as these programs have many different features that u might like
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